Radiative Processes in Astrophysics

Radiative Processes in Astrophysics 

Course Code: 031M1001H

Course Name: Radiative Processes in Astrophysics 

Credits: 3.0

Level: Senior and graduate

Pre-requisite: Intermediate electromagnetic theory, special relativity, introductory quantum mechanics

Lecture Time: 60 hours

Instructors: Bifang Liu

Course Description

The course is designed for seniors or first-year graduate students of astronomy, astrophysics, and related physics. The students should have good physics background, including introductory quantum mechanics, intermediate electromagnetic theory, special relativity, and some statistical mechanics. The course covers classical and quantum electromagnetic radiative processes, and radiative transfer relevant to astrophysics. It is concentrated on understanding the physics in all kinds of radiative processes. Application of the theory to astronomical systems is emphasized.

The basic requirement of this course is that students should have fundamental knowledge of radiative processes, radiative transfer during the propagation. In addition, students should learn how to use the theory to investigate the observational phenomena in astronomical systems.


Chapter 1 Fundamentals of Radiative Transfer

  1. 1Fundamental Definitions
  2. 2Radiative Transfer
  3. 3Thermal Radiation
  4. 4The Einstein Coefficients
  5. 5Scattering Effects; Random Walks
  6. 6Radiative Diffusion

Chapter 2 Basic Theory Of Radiation Fields

  1. 1Review of Maxwell’s Equations
  2. 2Plane Electromagnetic Waves
  3. 3The Radiation Spectrum
  4. 4Polarization and Stokes Parameters
  5. 5Electromagnetic Potentials

Chapter 3 Radiation From Moving Charges

  1. 1Retarded Potentials of Single Moving Charges: The Lienard-Wiechart Potentials
  2. 2The Velocity and Radiation Fields
  3. 3Radiation from Nonrelativistic Systems of Particles

Chapter 4 Relativistic Covariance And Kinematics

  1. 1Review of Lorentz Transformations
  2. 2Four-Vectors
  3. 3Covariance of Electromagnetic Phenomena
  4. 4Fields of a Uniformly Moving Charge
  5. 5Relativistic Mechanics and the Lorentz Four-Force
  6. 6Emission from Relativistic Particles

Chapter 5 Bremsstrahlung

  1. 1Emission from Single-Speed Electrons
  2. 2Thermal Bremsstrahlung Emission
  3. 3Thermal Free-Free Absorption
  4. 4Relativistic Bremsstrahlung
  5. 5From Bremsstrahlung to Blackbody

Chapter 6 Synchrotron Radiation

  1. 1Cyclotron Emission
  2. 2The Power ans Spectrum of Synchrotron Radiation
  3. 3Spectral Index for Power-Law Electron Distribution
  4. 4Polarization of Synchrotron Radiation
  5. 5Transition from Cyclotron to Synchrotron Emission
  6. 6Synchrotron Self-Absorption
  7. 7Curvature Radiation

Chapter 7 Compton Scattering

  1. 1Thomson scatteringCompton Scattering and Inverse Compton Scattering
  2. 2Inverse Compton Power for Single Scattering
  3. 3Inverse Compton Spectra for Single Scattering
  4. 4Energy Transfer for Repeated Scatterings in a Finite, Thermal Medium: The Compton Y Parameter
  5. 5Inverse Compton Spectra and Power for Repeated Scatterings by Relativistic Electrons of Small Optical Depth
  6. 6Repeated Scatterings by Nonrelativistic Electrons: The Kompaneets Equation
  7. 7Spectral Regimes for Repeated Scattering by Nonrelativistic Electrons

Chapter 8 Radiative Processes in Astrophysical Systems

  1. 1Synchrotron Self–Compton Scattering
  2. 2Radiative Processes in Accretion Flows
  3. 3Radiative Processes in Active Galactic Nuclei

Chapter 9 Radiative Recombination

  1. 1Recombination Radiation
  2. 2Bound-Free Absorption
  3. 3Recombination Line
  4. 4Fluorescence Iron Kα Line

Chapter 10 Plasma Effects

  1. 1Dispersion in Cold, Isotropic Plasma
  2. 2Propagation Along a Magnetic Field; Faraday Rotation
  3. 3Plasma Effects in High-Energy Emission Processes

         Cherenkov Radiation, Razin Effect


The grades include final examination and assignments of weekly homework


Rybicki,G.B. and Lightman,A.P. , Radiative Processes in Astrophysics, John Wiley & Sons, 1979


[1] Ghisellini, G., Radiative Processes in High Energy Astrophysics, Lecture Notes in Physics, Volume 873, Springer International Publishing, 2013

[2] You. J. H., Radiative Mechanisms in Astrophysics, Science Press, 1998 (Chinese version)